Arbuscular mycorrhizal fungi as a tool to ameliorate the phytoremediation potential of poplar: biochemical and molecular aspects

Poplar is a suitable species for phytoremediation, able to tolerate high concentrations of heavy metals (HMs). Arbuscular mycorrhizal fungi (AMF) form symbiotic associations with the roots of most land plants; they improve nutrient uptake and enhance phytoextraction of HMs while alleviating stress in the host plant. This review summarizes previous results from field and greenhouse studies conducted by us and dealing with this topic. In a field trial on a highly Zn- and Cu-contaminated site, differences in plant survival and growth were observed among 168 clones originating from natural populations of Populus alba L. and Populus nigra L. from northern Italy. After two and a half years from planting, the density, activity and metabolic versatility of the culturable fraction of the soil bacteria in the HM-polluted field was higher in the soil close to where larger poplar plants were growing, in spite of comparable HM concentrations recorded in these soils. One well-performing clone of P. alba (AL35), which accumulated a higher concentration of both metals and had high foliar polyamine (PA) levels, was used for further investigation. In a greenhouse study, AL35 cuttings pre-inoculated with AMF (Glomus mosseae or Glomus intraradices) and then transferred to pots containing soil, collected from the HM-polluted site, displayed growth comparable to that of controls grown on unpolluted soil, in spite of higher Cu and Zn accumulation. Such plants also showed an overall up-regulation of metallothionein (MT) and PA biosynthetic genes, together with increased PA levels. A genome-wide transcriptomic (cDNA-AFLP) analysis allowed the identification of a number of genes, mostly belonging to stress-related functional categories of defense and secondary metabolism, that were differentially regulated in mycorrhizal vs. non mycorrhizal plants. A proteomic analysis revealed that, depending on sampling time, changes in protein profiles were differentially affected by AMF and/or HMs. It is concluded that soil-borne microorganisms affect plant performance on HM-polluted soil. In particular, mycorrhizal plants exhibited increased capacity for phytostabilization of HMs, together with improved growth. Their greater stress tolerance may derive from the protective role of PAs, and from the strong modulation in the expression profiles of stress-related genes and proteins

Neoadjuvant and adjuvant doxorubicin chemotherapy in a case of feline soft tissue sarcoma

A 7-year old male neutered domestic shorthair cat was presented with a 2 month history of a slow-growing mass on the right zygomatic area. A CT scan revealed a soft tissue mass in the right zygomatic region with no alterations of the underlying bone and features of local invasiveness. Cytology was suggestive of a mesenchymal tumour and histopathology from an incisional biopsy was consistent with a soft tissue sarcoma (STS). The cat was treated with neoadjuvant intravenous doxorubicin chemotherapy at a dose of 25 mg/m2, every two weeks. The patient experienced a partial response and underwent surgical excision of the tumour. Doxorubicin was continued as an adjuvant treatment for three further chemotherapy sessions, at a dose of 25 mg/m2 every 21 days. Local tumour recurrence was detected on clinical examination and cytologically confirmed 259 days following surgery

Quantitative estimation of antibodies in the immunoglobulin classes of the mouse. I. Effect of adjuvants on the antibody response to human serum albumin and keyhole limpet haemocyanin

Antibody activity against HSA and KLH was present in all five immunoglobulin classes of BALB/c mice. Bordetella pertussis vaccine was more effective in stimulating antibody production against HSA than against KLH and IgG(1) and IgG(2b) antibody were affected more than the antibody present in the other immunoglobulin classes. The results are discussed in relation to the differing thymic dependence of these two antigens

Calcolo della paratia con tirante infissa in terreno elasto-plastico

Viene illustrato un metodo per l'analisi non lineare di un paratia ancorata con un tirante ed infissa in un terreno elasto-plastic